Collagen sponge (CS), highly crosslinked, with large pore size and high resilience, is readily permeated by cells, vessels and cell products after implantation in tissue. It has controllable rate of resorption and no detectable antigenicity. Because of these and other unique characteristics, we propose to study the biomedical aspects of using CS as a burn dressing, temporary substitute for bone and articular cartilage. Animal models of clean and septic third degree burns in rabbits and pigs, defects of bone and articular cartilage in dogs and pigs will be induced and collagen sponge tested in comparison with other competitive biomaterials and in appropriate application. A complex of surgical, biological, morphological, and biochemical methods will be used to evaluate the dynamics of wound healing. Several basic problems involved in using CS will be tested, such as the role of pore size, resilience, rate of resorption on cell ingrowth, etc. The final goal is to find the real value of CS as biomaterial for medical application.